The future prospects of multi-party democracy in Africa

Paper presented at the Wits History Workshop: Democracy, Popular Precedents, Practice and Culture, 13-15 July, 199

Reason and Sagacity in Africa: Odera Oruka’s Contribution to Philosophy

Commentators on the four trends in contemporary African philosophy as enunciated by H. Odera Oruka frequently focus on the merits and demerits of each trend. However, many of them are obblivious to the way in which sagacity emancipates African philosophy by putting reason in its rightful pivotal position. This article argues that while the professional philosophers accused ethno-philosophers of doing disservice to African philosophy, they too stand accused of the same. This is due to the fact that both ethno-philosophy and professional philosophy function within the Western grid and therefore in the interest and service of the Western world. Philosophic sagacity, the article argues, discards the undesirable elements of ethno-philosophy and professional philosophy, while retaining desirable ones, namely, the Africanness in ethno-philosophy and the objectivity in professional philosophy. Because philosophic sagacity is African and objective, it is a desired tool of change in Africa. It can, for example, be used to address negative aspects of ethnicity that bedevil Africa. There lies the most important contribution by H. Odera Oruka to philosophy in general and African philosophy in particular. Key Words Odera Oruka, philosophic sagacity, ethno-philosophy, professional philosophy, reaso

Antifungal activity of crude extracts of Gladiolus dalenii van Geel (Iridaceae)

Bulb extracts of Gladiolus dalenii reportedly used in the treatment of fungal infections in HIV/AIDS patients in the Lake Victoria region were tested for antifungal activity using the disc diffusion assay technique. Commercially used antifungal drugs, Ketaconazole and Griseofulvin (Cosmos Pharmaceuticals) were used as standards. Dichloromethane (CH2CL2)/Methanol (MeOH) in the ratio 1:1. Soluble extracts showed antifungal activity against Aspergillus niger. Direct bioautography on silica gel Thin Layer Chromatography (TLC) and appropriate spraying agents were used to identify the active component in the extract. The activities of both the extracts were higher than that of Griseofulvin. CH2CL2 soluble extract in addition showed ability to delay sporulation in A.niger. The active group of compounds in the extracts was identified as alkaloids, which offer immense potential for development of new and valuable pharmaceutical products.Key words: G. dalenii, Aspergillus niger, Antifungal activit

Estimation Of Reference Crop Evapotranspiration Using Fuzzy State Models

Daily evapotranspiration (ET) rates are needed for irrigation scheduling. Owing to the difficulty of obtaining accurate field measurements, ET rates are commonly estimated from weather parameters. A few empirical or semi–empirical methods have been developed for assessing daily reference crop ET, which is converted to actual crop ET using crop coefficients. The FAO Penman–Monteith method, which is now accepted as the standard method for the computation of daily reference ET, is sophisticated. It requires several input parameters, some of which have no actual measurements but are estimated from measured weather parameters. In this study, we examined the suitability of fuzzy logic for estimating daily reference ET with simpler and fewer parameters. Two fuzzy evapotranspiration models, using two or three input parameters, were developed and applied to estimate grass ET. Independent weather parameters from sites representing arid and humid climates were used to test the models. The fuzzy estimated ET values were compared with direct ET measurements from grass–covered weighing lysimeters, and with ET estimations obtained using the FAO Penman–Monteith and the Hargreaves–Samani equations. The estimated ET values from a fuzzy model using three input parameters (Syx = 0.54 mm, r2 = 0.90) were found to be comparable to ET values estimated with the FAO Penman–Monteith equation (Syx = 0.50 mm, r2 = 0.91) and were more accurate than those obtained by the Hargreaves–Samani equation (Syx = 0.66 mm, r2 = 0.53). These results show that fuzzy evapotranspiration models with simpler and fewer input parameters can yield accurate estimation of ET

Evaluation Of Methods For Estimating Daily Reference Crop Evapotranspiration At A Site In The Humid Southeast United States

Estimated daily reference crop evapotranspiration (ETo) is normally used to determine the water requirement of crops using the crop factor method. Many ETo estimation methods have been developed for different types of climatic data, and the accuracy of these methods varies with climatic conditions. In this study, pair−wise comparisons were made between daily ETo estimated from eight different ETo equations and ETo measured by lysimeter to provide information helpful in selecting an appropriate ETo equation for the Cumberland Plateau located in the humid Southeast United States. Based on the standard error of the estimate (Syx), the relationship between the estimated and measured ETo was the best using the FAO−56 Penman−Monteith equation (coefficient of determination (r2) = 0.91, Syx = 0.31 mm d−1, and a coefficient of efficiency (E) = 0.87), followed by the Penman (1948) equation (r2 = 0.91, Syx = 0.34 mm d−1, and E = 0.88), and Turc’s equation (r2 = 0.90, Syx = 0.36 mm d−1, and E = 0.88). The FAO−24 Penman and Priestly−Taylor methods overestimated ETo, while the Makkink equation underestimated ETo. The results for the Hargreaves−Samani equation showed low correlation with lysimeter ETo data (r2 = 0.51, Syx = 0.68 mm d−1, and E = 0.20), while those for the Kimberly Penman were reasonable (r2 = 0.87, Syx = 0.40 mm d−1, and E = 0.87). These results support the adoption of the FAO−56 Penman−Monteith equation for the climatological conditions occurring in the humid Southeast. However, Turc’s equation may be an attractive alternative to the more complex Penman−Monteith method. The Turc method requires fewer input parameters, i.e., mean air temperature and solar irradiance data only

Intra-myocardial Bullet causing heart block in a patient with multiple gunshot wounds: Case Report

Elective removal of intra-myocardial bullet remains a controversial subject. A non-operative approach has been recommended as appropriate for a stable asymptomatic patient. In the presence of complications such as bleeding, perforation leading to cardiac tamponade, thrombus formation, embolization, rhythm disturbances and infections, surgical removal may be advised. We present a patient who survived multiple gunshot wounds with a bullet lodged in the wall of the left ventricle of the heart. Details of the injuries sustained, operative removal of the bullet and the challenges that ensued are illustrated

Autopsy Findings on a Pair of Dicephalic Parapagus Twins: A Case Report

Conjoined twins are a rare occurrence that presents significant challenges to both parents and medical care givers with many theories being advanced to explain this occurrence.“Parapagus” is a fairly recent term, in which the twins lie side by side with ventro-lateral fusion and are extremely rare representing 0.5% of all reported cases. We present a case report on post mortem findings on a set of parapagus twins delivered through caesarian section at Narok district hospital. We illustrate the various anomalies of the thoracic, abdominal cavity and central nervous system and discuss the embryologic etiologic theories.Key Words: Conjoined, Dicephalic, Malformations, Autops

Directly observed road safety compliance by Motor Cycle Riders after a 5- Year Road Safety Campaign in Naivasha, Kenya

Objective: To assess the extent of compliance with road safety regulations by  motorcycle riders following a five year road safety campaign in Naivasha town, Kenya.Design: A cross sectional study.Setting: Naivasha town, Nakuru county, Kenya.Results: A total of 9,280 MCs ferrying 13,733 people were observed. Less than 1% complied with all the four road safety  requirements. The overall helmet wearing compliance was 31%. MC driver helmet compliance was 42% which was five timeshigher than passenger helmet compliance. Female passengers were twice less likely to wear helmet than males.Conclusion: Despite the five-year road safety campaign, compliance among MC users remains low particularly among the passengers and more so female passengers. Does Kenya need to rethink the motor cycle road safety policy

Optimization Of Fuzzy Evapotranspiration Model Through Neural Training With Input–Output Examples

In a previous study, we demonstrated that fuzzy evapotranspiration (ET) models can achieve accurate estimation of daily ET comparable to the FAO Penman–Monteith equation, and showed the advantages of the fuzzy approach over other methods. The estimation accuracy of the fuzzy models, however, depended on the shape of the membership functions and the control rules built by trial–and–error methods. This paper shows how the trial and error drawback is eliminated with the application of a fuzzy–neural system, which combines the advantages of fuzzy logic (FL) and artificial neural networks (ANN). The strategy consisted of fusing the FL and ANN on a conceptual and structural basis. The neural component provided supervised learning capabilities for optimizing the membership functions and extracting fuzzy rules from a set of input–output examples selected to cover the data hyperspace of the sites evaluated. The model input parameters were solar irradiance, relative humidity, wind speed, and air temperature difference. The optimized model was applied to estimate reference ET using independent climatic data from the sites, and the estimates were compared with direct ET measurements from grass–covered lysimeters and estimations with the FAO Penman–Monteith equation. The model–estimated ET vs. lysimeter–measured ET gave a coefficient of determination (r2) value of 0.88 and a standard error of the estimate (Syx) of 0.48 mm d–1. For the same set of independent data, the FAO Penman–Monteith–estimated ET vs. lysimeter–measured ET gave an r2 value of 0.85 and an Syx value of 0.56 mm d–1. These results show that the optimized fuzzy–neural–model is reasonably accurate, and is comparable to the FAO Penman–Monteith equation. This approach can provide an easy and efficient means of tuning fuzzy ET models

Weed Dynamics during Transition to Conservation Agriculture in Western Kenya Maize Production

Weed competition is a significant problem in maize (Zea mays, L.) production in Sub-Saharan Africa. Better understanding of weed management and costs in maize intercropped with beans (Phaseolus vulgaris, L.) during transition to conservation agricultural systems is needed. Changes in weed population and maize growth were assessed for a period of three years at Bungoma where crops are grown twice per year and at Trans-Nzoia where crops are grown once per year. Treatments included three tillage practices: minimum (MT), no-till (NT) and conventional (CT) applied to three cropping systems: continuous maize/bean intercropping (TYPICAL), maize/bean intercropping with relayed mucuna after bean harvest (RELAY) and maize, bean and mucuna planted in a strip intercropping arrangement (STRIP). Herbicides were used in NT, shallow hand hoeing and herbicides were used in MT and deep hoeing with no herbicides were used in CT. Weed and maize performance in the maize phase of each cropping system were assessed at both locations and costs of weed control were estimated at Manor House only. Weed density of grass and forb species declined significantly under MT and NT at Manor House and of grass species only at Mabanga. The greatest declines of more than 50% were observed as early as within one year of the transition to MT and NT in STRIP and TYPICAL cropping systems at Manor House. Transitioning to conservation based systems resulted in a decline of four out of five most dominant weed species. At the same time, no negative impact of MT or NT on maize growth was observed. Corresponding costs of weed management were reduced by $148.40 ha-1 in MT and$149.60 ha-1 in NT compared with CT. In conclusion, farmers can benefit from effective and less expensive weed management alternatives early in the process of transitioning to reduced tillage operations